The proposed longitudinal study will follow a cohort of 36 children identified at age two as 'slow' in the development of expressive language. The subjects were matched to a group of 36 normal speakers on the basis of age, sex, SES, and race. At 24-32 months these subjects were all given an intensive battery of language, cognitive, and behavioral assessments. These data - already collected - comprise the baseline for the proposed longitudinal study. The purposes of the proposed study are 1) to determine if and when the "slow starters" move within the normal range of language development, and 2) to identify language, behavioral, and cognitive variables at age two that predict which children with slow language acquisition will go on to show chronic language delay or learning disability in the early school years. The subjects will be seen for four yearly evaluations of language development, and, in the final three years, school readiness and achievement. Analysis of variance will be used to identify factors in the baseline evaluation that differentiate the two groups. These factors will be used as predictors of language and school achievement outcomes, using multiple regression procedures. The results will contribute to a better understanding of the range of normal variation in early language development. They will also aid in making cost-effective decisions about early intervention for toddlers and pre-schoolers who show slow language growth.